Daytona clone Vega hatch question

[70 sublime]

I have a chance to pick up a hatch but it has a fiberglass flare glued on it
Just wondering if the there may be a rust issue hiding under it is why it was added

When using the Vega hatch on a clone car how much gets trimmed off the hatch to make it fit ?

Is all the flat part used and just the lip that curves under on the back edge removed ?

[DAY CLONA]

If you want to position the hatch for correct window placement, you'll need approx 12-13 inches of sheetmetal from the bottom of the GLASS EDGE to the shortened trunk edge, you'll need to fabricate a 3-4" wide panel ABOVE the TOP GLASS EDGE to seal up to the stock Charger roof line, as the Vega hatch has little meat above the top of the glass

[XS29L9B2]

I mademy daytona with a vega hatch  it s a great solution